The Research Methods Core (RMC) of the P20 addresses a number of methodological issues that are raised in the study of adaptive interventions. These include: [unreadable] Identification of optimal time-varying tailoring variables that trigger modifications in treatment [unreadable] Study of mechanisms of action and mediation effects within adaptive treatments [unreadable] Development of computer systems to facilitate implementation of complex adaptive interventions [unreadable] Development of methods to assess and study within-session treatment process in adaptive interventions Further progress on these methodological issues is necessary to improve the feasibility and effectiveness of adaptive interventions. Moreover, this work will inform the analyses of data from the Developmental Projects. The Research Methods Core (RMC) of the P20 addresses a number of methodological issues that are raised in the study of adaptive interventions. These include: [unreadable] Identification of optimal time-varying tailoring variables that trigger modifications in treatment [unreadable] Study of mechanisms of action and mediation effects within adaptive treatments [unreadable] Development of computer systems to facilitate implementation of complex adaptive interventions [unreadable] Development of methods to assess and study within-session treatment process in adaptive interventions Further progress on these methodological issues is necessary to improve the feasibility and effectiveness of adaptive interventions. Moreover, this work will inform the analyses of data from the Developmental Projects. In the Principal Research Core (PRC), the Developmental Projects address issues at specific points in our conceptual model (see Projects 1-3 in Figure 1). Project 1 is focused on whether access to and engagement in evidence-based alcohol treatment for primary care patients with alcohol dependence can be increased through the use of a nonspecialty care approach, and consideration of patient preference and modifications to treatment for nonresponders. This model, referred to as Alcohol Care Management, includes telephone- based assessment and monitoring, pharmacotherapy, and psychosocial support. Therefore, Project 1 addresses the links in our conceptual model between identification in primary care, initial engagement, and acute care. Project 2, on the other hand, is focused on increasing engagement and retention in patients who undergo an intake evaluation in a specialty care program. This project will determine whether offering patients who fail to engage in specialty care the choice of several alternative approaches produces higher rates of engagement and continued participation than further efforts to engage them in specialty care only. This project will also test a telephone-based procedure for re-engaging patients who achieved initial engagement in specialty care but subsequently dropped out. Both projects will also examine whether the experimental conditions lead to better short-term alcohol use outcomes, in addition to better engagement and retention. Moreover, both projects now feature sequential randomizations designs, which are recommended by Murphy et al. (2007) for the development of adaptive algorithms. Project 3 is an initial evaluation of the feasibility and utilization of a highly innovative, web-based adaptive continuing care program developed by the Hazelden Foundation, a premier non-profit provider of residential treatment in Minnesota